-- Hoogle documentation, generated by Haddock
-- See Hoogle, http://www.haskell.org/hoogle/


-- | Type-safe, non-relational, multi-backend persistence.
--   
@package persistent-template
@version 2.1.3


-- | This module provides utilities for creating backends. Regular users do
--   not need to use this module.
module Database.Persist.TH

-- | Converts a quasi-quoted syntax into a list of entity definitions, to
--   be used as input to the template haskell generation code (mkPersist).
persistWith :: PersistSettings -> QuasiQuoter

-- | Apply <a>persistWith</a> to <a>upperCaseSettings</a>.
persistUpperCase :: QuasiQuoter

-- | Apply <a>persistWith</a> to <a>lowerCaseSettings</a>.
persistLowerCase :: QuasiQuoter

-- | Same as <a>persistWith</a>, but uses an external file instead of a
--   quasiquotation.
persistFileWith :: PersistSettings -> FilePath -> Q Exp

-- | Create data types and appropriate <a>PersistEntity</a> instances for
--   the given <a>EntityDef</a>s. Works well with the persist quasi-quoter.
mkPersist :: MkPersistSettings -> [EntityDef] -> Q [Dec]

-- | Settings to be passed to the <a>mkPersist</a> function.
data MkPersistSettings

-- | Which database backend we're using.
--   
--   When generating data types, each type is given a generic version-
--   which works with any backend- and a type synonym for the commonly used
--   backend. This is where you specify that commonly used backend.
mpsBackend :: MkPersistSettings -> Type

-- | Create generic types that can be used with multiple backends. Good for
--   reusable code, but makes error messages harder to understand. Default:
--   True.
mpsGeneric :: MkPersistSettings -> Bool

-- | Prefix field names with the model name. Default: True.
mpsPrefixFields :: MkPersistSettings -> Bool

-- | Generate <tt>ToJSON</tt>/<tt>FromJSON</tt> instances for each model
--   types. If it's <tt>Nothing</tt>, no instances will be generated.
--   Default:
--   
--   <pre>
--   Just EntityJSON
--       { entityToJSON = 'keyValueEntityToJSON
--       , entityFromJSON = 'keyValueEntityFromJSON
--       }
--   </pre>
mpsEntityJSON :: MkPersistSettings -> Maybe EntityJSON

-- | Instead of generating normal field accessors, generator lens-style
--   accessors.
--   
--   Default: False
--   
--   Since 1.3.1
mpsGenerateLenses :: MkPersistSettings -> Bool
data EntityJSON
EntityJSON :: Name -> Name -> EntityJSON

-- | Name of the <tt>toJSON</tt> implementation for <tt>Entity a</tt>.
entityToJSON :: EntityJSON -> Name

-- | Name of the <tt>fromJSON</tt> implementation for <tt>Entity a</tt>.
entityFromJSON :: EntityJSON -> Name

-- | Create an <tt>MkPersistSettings</tt> with default values.
mkPersistSettings :: Type -> MkPersistSettings

-- | Use the <tt>SqlPersist</tt> backend.
sqlSettings :: MkPersistSettings

-- | Same as <a>sqlSettings</a>.
--   
--   Since 1.1.1

-- | <i>Deprecated: use sqlSettings</i>
sqlOnlySettings :: MkPersistSettings

-- | Creates a single function to perform all migrations for the entities
--   defined here. One thing to be aware of is dependencies: if you have
--   entities with foreign references, make sure to place those definitions
--   after the entities they reference.
mkMigrate :: String -> [EntityDef] -> Q [Dec]

-- | Save the <tt>EntityDef</tt>s passed in under the given name.
mkSave :: String -> [EntityDef] -> Q [Dec]

-- | Generate a <a>DeleteCascade</a> instance for the given
--   <tt>EntityDef</tt>s.
mkDeleteCascade :: MkPersistSettings -> [EntityDef] -> Q [Dec]

-- | Apply the given list of functions to the same <tt>EntityDef</tt>s.
--   
--   This function is useful for cases such as:
--   
--   <pre>
--   &gt;&gt;&gt; share [mkSave "myDefs", mkPersist sqlSettings] [persistLowerCase|...|]
--   </pre>
share :: [[EntityDef] -> Q [Dec]] -> [EntityDef] -> Q [Dec]

-- | Automatically creates a valid <a>PersistField</a> instance for any
--   datatype that has valid <a>Show</a> and <a>Read</a> instances. Can be
--   very convenient for <a>Enum</a> types.
derivePersistField :: String -> Q [Dec]

-- | Automatically creates a valid <a>PersistField</a> instance for any
--   datatype that has valid <a>ToJSON</a> and <a>FromJSON</a> instances.
--   For a datatype <tt>T</tt> it generates instances similar to these:
--   
--   <pre>
--   instance PersistField T where
--       toPersistValue = PersistByteString . L.toStrict . encode
--       fromPersistValue = (left T.pack) . eitherDecodeStrict' &lt;=&lt; fromPersistValue
--   instance PersistFieldSql T where
--       sqlType _ = SqlString
--   </pre>
derivePersistFieldJSON :: String -> Q [Dec]

-- | produce code similar to the following:
--   
--   <pre>
--   instance PersistEntity e =&gt; PersistField e where
--      toPersistValue = PersistMap $ zip columNames (map toPersistValue . toPersistFields)
--      fromPersistValue (PersistMap o) = 
--          let columns = HM.fromList o
--          in fromPersistValues $ map (name -&gt;
--            case HM.lookup name columns of
--              Just v -&gt; v
--              Nothing -&gt; PersistNull
--      fromPersistValue x = Left $ "Expected PersistMap, received: " ++ show x
--      sqlType _ = SqlString
--   </pre>
persistFieldFromEntity :: MkPersistSettings -> EntityDef -> Q [Dec]
packPTH :: String -> Text
lensPTH :: (s -> a) -> (s -> b -> t) -> Lens s t a b
instance [overlap ok] Show SqlTypeExp
instance [overlap ok] Show EntityDefSqlTypeExp
instance [overlap ok] Lift SqlType
instance [overlap ok] Lift PersistUpdate
instance [overlap ok] Lift PersistFilter
instance [overlap ok] Lift FieldType
instance [overlap ok] Lift DBName
instance [overlap ok] Lift HaskellName
instance [overlap ok] Lift' a => Lift a
instance [overlap ok] (Lift' k, Lift' v) => Lift' (Map k v)
instance [overlap ok] Lift' a => Lift' [a]
instance [overlap ok] Lift' Text
instance [overlap ok] Lift ForeignDef
instance [overlap ok] Lift CompositeDef
instance [overlap ok] Lift UniqueDef
instance [overlap ok] Lift FieldDef
instance [overlap ok] Lift EntityDef
instance [overlap ok] Lift EmbedFieldDef
instance [overlap ok] Lift EmbedEntityDef
instance [overlap ok] Lift ReferenceDef
instance [overlap ok] Lift EntityDefSqlTypeExp
instance [overlap ok] Lift FieldSqlTypeExp
instance [overlap ok] Lift FieldsSqlTypeExp
instance [overlap ok] Lift SqlTypeExp